I have several .eml email files to import. Some of them were saved as quoted-printable 7-bit encoded.

I skipped through the Mathematica documentation and found ToCharacterCode and CharacterEncoding. However,

Import[foo.eml, CharacterEncoding -> "PrintableASCII"]

does not lead to conversion of the 7-bit characters to the default set (8-bit I guess).

In particular, I want to get rid of encodings like =FC, which is a German Umlaut-u (ü). After that I would like to be able to proceed with normal text analysis. Does anybody have experience with the right functions?

The "Math1" argument of FromCharacterCode could perhaps be dropped. I used it in the context of the MathGroup where a lot of Mathematica symbols got quoted printabled. For normal text, the default translation should be fine.

Great solution. What a pity that the Import[] does not auto. convert the characters. Other languages have their function for this:-( -- btw: works with ease.
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FrankMay 26 '13 at 16:25

Yesterday I found out, that the German a-Umlaut is translated to an imaginary part double-i. I removed the parameter "Math1" and obtained the correct result. Moreover, in my case the equal sign at the end of the line introduced a line wrap at column 75. Thus I changed the 2nd rule to "=\n" -> ""
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FrankMay 28 '13 at 8:27

prompted me to post this answer, to mostly serve as a nudge/reminder that in case you're stuck at a problem and know how to do it in of the several other languages that can be interfaced with Mathematica, then the most productive use of your time would be to quickly whip it up in language X and use it inside Mathematica using the appropriate X-Link application. In that spirit, I'll present the following simple solution using Java/JLink:

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